They wouldn't be a good therapist if they judged you, and even more, acted negatively towards anything you could say. If anything, they should be unfazed. The more you tell, the more they can understand and therefore help you.

I've only told a few people my deepest secrets. Every time I did, I broke down COMPLETELY the next day, in so much pain I could barely stand it. But that pain will pass. I think the shock of saying it out loud is so extreme that it's hard to process, but it WILL pass if you let it. Please stay strong. You're on the right track.